The innovation is directed to a housing for an electrical component, particularly for a relay, comprising a cuboid cap whose outside wall is set back at the upper side in the region of a corner, whereby a projection projects out at the setback wall part, a channel that is in communication with the interior of the housing but that is closed by the outside wall of the projection being formed in the projection.
It is important in such components, i.e. particularly in electro-magnetic relays, that the housing for integration on printed circuit boards be at least wash-tight so that liquids and vapors cannot penetrate into the interior and deteriorate the contact surfaces when cleaning the printed circuit boards or during other manufacturing procedures. This is usually accomplished in that a plastic cap is glued to a pedestal or to a base member, is welded thereto or is tightly connected thereto in some other way.
This termination of the housing achieved with plastic, however, can be disadvantageous for the further useful life of a relay or of a similar component under certain conditions since the plastic housing, the coil and other parts in the relay emit eliminations over the course of time that are injurious to contacting and the generate a micro-climate inside the closed housing over a longer time, this micro-climate being potentially more harmful to the contacts than the normal, outside air. It is therefore also frequently desirable to provide the housing with an aeration opening after the integration of a relay and after the washing of the printed circuit board, this aeration opening enabling a communication between the interior of the housing and the outside atmosphere and thus also creating a pressure balancing given temperature fluctuations. This, however, should be implementable in an optimally simple way; it should also be assured that no function parts are damaged or negatively affected by the introduction of the aeration opening and that no particles of plastic fall into the inside where they could deposit on the contact surfaces.
For this said purpose, it is known in a relay housing of the species initially cited (European Published Application No. 00 58 727) to set a corner at the upper side of the cap back somewhat so that a step arises, whereby a cylindrical projection having an internally disposed channel is formed on this step. The internally disposed channel can be opened toward the outside by cutting the cylindrical projection off.
This known structure, however, has the disadvantage that the offset step lies parallel to the upper side of the cap, so that a cut parallel to this upper side but at a somewhat lower position is required for cutting the projecting peg off. Given a higher packing density of relays on a printed circuit board, the projection that is to be cut off is difficult to access and can only be accessed with a special tool.